Xtset Stata Example. Below is an example of an autoregressive 1 covariance matrix. Xtset panelvar xtset panelvar timevar.
In addition to the covariance structures shown above stata also offers the following covariance structures. In the future please post example data using the dataex command. Tell stata once after which all survival analysis commands the st commands will use this information.
For example after using stset a cox proportional hazards model with age and sex as covariates can be fltted using.
I have checked and i have zero missing observations on country company and year. Xtset panelvar xtset panelvar timevar. Some other commands like clogit can also sometimes be used. In the future please post example data using the dataex command.
